That's kind of a leap, and an obfuscation of a relatively straightforward concept.
A "freedom of speech" right doesn't give me anything I don't already have. That is, I can already speak, and say basically anything I want. It just so happens to be codified in US law. You'll note that it says nothing about a freedom to speak at a high level, a freedom to persuade, or even a freedom to have people listen.
The "right to not be imprisoned without a fair trial" is a negative right (if you're suspected of a crime, we will imprison you) with limitations (but you'll get a fair trial). The right to a fair trial is not a positive right, it's a limit on a negative right.
You can think of negative rights as restricting natural rights. There's no natural barrier to me taking a steaming shit on the sidewalk in front of the white house. There are negative rights, however, that restrict my ability to do that.
Positive rights provide you with something you don't already have. A right to health care, for instance, will provide me with access to medicine, doctors, and other services I might otherwise have to go out and find on my own.
Negative rights generally have more obvious consequences (and repercussions) than positive rights, which is why I and many others like to make this distinction.